1. Field of the Invention
The present invention relates to a memory card for use in a personal computer (hereinafter referred to as "PC") or a personal digital assistant (hereinafter referred to as "PDA"). Particularly, the invention relates to a memory card adaptor card which allows for installation of a smaller size memory card into a memory card slot of a PC for electrical connection therebetween.
2. Description of Related Art
PC cards conventionally available for PCs and PDAs are standardized by PCMCIA/JEIDA, which specifies the outer dimensions thereof as being 85.6 mm.times.54.0 mm.times.5.0 mm (length.times.width.times.thickness).
With the size reduction of information devices including PCs and PDAs, smaller size memory cards have been proposed. For example, such a smaller size memory card has a length of 45.0 mm, a width of 42.8 mm and a thickness of 3.3 mm. Attempts have been made to use such new smaller size memory cards in conventional PC card slots which are dominant in the market.
In this connection, memory card adaptor cards have been put to practical application, which allows for installation of a smaller memory card in a memory card slot compliant with a different standard for connection therebetween.
Memory cards often hold significant electrostatic charges before installation thereof into memory card slots. Therefore, it is useful to provide a grounding circuit for dissipating the electrostatic charges prior to connection of signal contacts of the memory card. A grounding device for a PC card is proposed, for example, in Japanese Examined Patent Publication No.8-31123 (1996).
However, an effective grounding mechanism applicable to a memory card adaptor card of a type as proposed by the present invention has not been developed yet. Therefore, a memory card adaptor card having a simple and reliable grounding device has long been desired.